Thyroid Function Test

A five-biomarker thyroid panel measuring TSH, free T3, free T4, anti-TPO, and anti-TG antibodies. Goes beyond the standard GP thyroid screen by including both active thyroid hormones and autoimmune markers. Results in 24 hours.

Most GP thyroid checks measure only TSH — and while this is a useful screening marker, it tells you nothing about the active thyroid hormones that tissues actually respond to, nor whether an autoimmune process is attacking the thyroid gland. This panel addresses both gaps by including the full functional and autoimmune picture in five markers. Free T3 and free T4 are the biologically active thyroid hormones. T4 is the primary output of the thyroid gland and must be converted to T3 (the more potent form) in peripheral tissues. Some individuals have normal TSH but impaired T4-to-T3 conversion, which standard TSH-only screening would miss entirely. The relationship between TSH and the free hormones provides substantially more diagnostic information than any single marker. Anti-TPO and anti-TG antibodies detect Hashimoto's thyroiditis and other autoimmune thyroid conditions, which are among the most common autoimmune disorders and can cause symptoms years before TSH moves outside the reference range. Early identification of thyroid autoimmunity allows for monitoring and timely intervention. At 60 pounds, this panel is remarkably cost-effective for the breadth it provides and is particularly valuable for individuals with a family history of thyroid disease, unexplained fatigue, weight changes, or mood disturbances.